The answer to this question is obviously going to vary depending on the way the answerer interprets current Republican politics. However, one of the reasons why this play is so excellent is the way in which it presents a cloak-and-dagger impression of politics that has truth throughout the ages, and in its presentation of power, arrogance and manipulation has much for us to learn and study in terms of our own understanding of politics.

The theme of absolute power is of course summarised in Caesar. He shows himself to be a very intelligent and capable individual. For example, he recognises the threat that Cassius represents when he emerges in this scene, however, his power has blinded him to such threats. This makes him vulnerable. Caesar is shown to desire to be a god and his ambition makes him weak, which is something that the conspirators can exploit. There do seem to be many parallels between Caesar and any number of politicians who, when given more power, allow that power to go to their heads and affect their judgement, making them vulnerable. I wouldn't want to point the finger at any one Republican politican, however!

Secondly, you might like to consider the role of rhetoric and manipulation in this play. Politics appears to be about the art of convincing other people to believe in what you want them to believe, and Cassius shows himself to be the true master of this art. In this famous manipulation scene, he expertly reads his victim and the way that Brutus already fears Caesar's power-hungry nature. He recognises that he can manipulate Brutus to join the conspirators based on the "good of Rome," appealing to the nobility of Brutus whilst actually only manipulating him for his own selfish ends. Notice what Cassius says in his soliloquy that closes this scene:

Well, Brutus, thou art noble; yet I see

Thy honourable mettle may be wrought

From that it is disposed; therefore it is meet

That noble minds keep ever with their likes;

For who so firm that cannot be seduced?

This scene more than any other in the play presents politics as being about the art of manipulation and reading your opponent and exploiting their virtues and weaknesses. The art of "spin" in today's politics is surely something that we can relate this to, as politics seems to be about presenting one "reality," however detached from reality it actually is.

There is currently definitely a fear that the Democrat in power may be taking too much power upon himself. There is also presently a decided effort among opposition Republicans to unseat him come the 2012 election. This corresponds to Act I, scene ii, predominantly between Brutus and Cassius, in that Cassius and Brutus are discussing their concerns over the incumbent and wondering how to unseat him.

One of the main complaints over the two party system employed in the US today is that the two main parties, Democrats and Republicans, work more against each than for the country. Their number one priority seems to be disparaging the other's name so their representatives win the election and obtain the majority positions of power in the government. That's what appears to be going on here as well. With the exception of Brutus, the conspirators seem only to care about getting their political rival, Caesar, out of power, not considering what that might do for their country. They are only unhappy with him because he defeated their representative Pompei. Meanwhile, Caesar has shown many examples of his ambitious and power hungry ways throughout his political career that shows he often acts on his own behalf rather than the country's.